It has become increasingly important to maintain communications connectivity in the presence of transmission system failures. To this end, path-switched ring type transmission systems and, more recently, bidirectional line-switched ring type transmission systems have been proposed that heal communications circuits in the presence of equipment failures, fiber cuts and node failures. Bidirectional line-switched ring transmission systems have a capacity advantage over path-switched ring transmission systems for all communications traffic patterns except a so-called simple hubbed traffic pattern, where the path-switched and line-switched ring transmission systems have the same capacity. On the other hand, a path-switched ring transmission system provides circuit presence at every ring node on the ring transmission system for each communications circuit being transported on the ring. In a bidirectional line-switched ring transmission system, circuit presence at every ring node for communications circuits propagating on the ring can only be established by employing twice the bandwidth as that used for the same communications circuits in the path-switched ring transmission system. Additionally, in the bidirectional line-switched ring transmission system, all service bandwidth is ring-protection-switched when necessary, and it is not possible to leave any of the bandwidth unprotected by ring switching.